bosch



F. P. BOSCH.

ROTARY PUMP.

APPLICATION FILED DEC. 11. 1915.

1 ,32 1,706 Patented Nov. 11, 1919.

2 SHEETSSHEET l.

4 F. P. BOSCH.

ROTARY'PUMP.

APPLICATION FILED DEC. 11. 19|5..

1 ,321,706. I Patented Nov. 11, 1919.

2 SHEETS-SHEET 2.

36 EancisCofib/Bosch Inventor v WW UNITED STATES PATENT oFFroE.

raANcIsco PBAT BOSCH, or BADALONA, sum.

ROTARY PUMP.

To all whom it may concern: 1

Be it known that I. FRANCISCO PRAT Boson, a subject of the King of Spain, residing at Badalona, Barcelona, inthe Kingdom ofSpain, have invented certain new and useful Improvements in Rotary Pumps; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in rotary pumps in which a drum provided with paddles is adapted to revolve in a casing, in eccentric relationship to the interior thereof. In pumps of .this character the paddles are arranged to slide in slots formed in the drum in such'a manner that their ends are always kept in contact with the inner surface of the casing whereby amore efficient propulsion of the liquid is attained.

The main object of this invention is to provide a pump in which the paddles of the drum are constantly kept in contact with the inner surface of the casing by the combined action of the centrifugal force imparted to the paddles and by the pressure of the liquid behind the paddles, the centrifugal force being the redominating factor in the attainment of tile above result.

Another object of this invention is to provide a pump in which the suction and discharge of the liquid are produced in two or more working chambers arranged symmetrically with respect to the drum, whereby an equalization of pressures to which the shaft of the pump issubjected is attained.

In accordance with this invention, the

drum is formed at its periphery with a bers are form plurality of slots inclined with respect to the corresponding radii of the drum and in which the paddles are adapted to slide. Each slot is cut away at its forward end exposing a portion of the forward end of the blade. The drum is also formed with a plurality of grooves whereof each communicates with the bottom of aslot. The inner surface of the pump-casing may be of such shape that.v will form with thedrum two or more we ing chambers, each of these communicating with the suction and discharge ipes. The working chamed with a cylindrical surface which at the central part of the chambers Specification of Letters Patent.

Patented Nov. 11, 1919..

Application filed December 11, 1915. Serial No. 66,376.

is concentric with the surface of the drum and diverges therefrom or converges therewith at the junctions of the chambers with the suction and discharge conduits.

Further objects and novel features of this invention will appear from the following detailed description, reference being had to the accompanying drawings, in which:

' Figure 1 is a cross section of a rotary pump according to this invention.

Fig. 2 is a sectional view of the same on the line II--II of Fig. 1.

Figs. 3 and 4 are front and side views (iieispectively of'the drum without the pad- Fig. 5 is a sectional view of a modified form of a pump on the line V-V of Fig. 6, and

Fig. 6 is a sectional view of the same on the hue VI'-VI of Fig. 5.

Referring to Figs. 1 to 4, 1 designates a casing and 16 a cover which may be secured to the casing by means of screws passing through the openings 25. The cas- 1 and the cover 16 are provided'with 1n -hl1%S 15-17, respectively, in which is jourshaft20 is formed with an outer extension 7 for receiving the rotary movement. The casmg 1 1s further provided with a suctionplpe 2 and a discharge pipe 3.'

The casing 1 is also formed with two lateral conduits 45 which establish communication between the pump body and the pipes 23.

A drum 7 is arranged eccentrically in the casing 1, and is tangential to the inner surface of the casing at the point 6, while the remainder of its outline forms with the casing a chamber 8 which corresponds to the eccentricity and determines the capacity of the pump.

In the pump-shown in Figs. 1 and 2, the

drum- 7 is provided with four paddles 11--'1213-14,.slidable in grooved slots 28 formed in the drum 7 and which are closed laterally by disks 910, secured to each face of the drum 7 by means of screws 22, thus forming a unitary structure. The slots 28 are cut away at their forward end, as at 27 and the bottom of each slot is in communication with a groove 26. The paddles 11-12-13 14 are preferably beveled and are so arranged as to form an acute angle with the direction of their movement. This angle may, of course, be varied according to the pressure which it is desired to maintain at the end of the paddle.

By revolving the .drum 7 in the direction of the arrow 24, suction is created behind the paddle which occupies the position 12 and the discharge of' the fluid in front thereof. This is due to the fact that the paddle is in contact with the surface 6' until it comes to the conduit 5 which communicates with the pipe 3 for the discharge of the liquid.

The water drawn by the pump fills the groove 26 and arriving at the slot 28 it acts upon the paddle forcing its edge against the inner surface of the casing. The centrifugal force, developed by the rotation of the drum also forces the paddle against the casing. In this manner the edge of the paddle is always kept in contact with the inner surface 6 of the casing 1, and furthermore the contact surface between the paddle and the casing is rendered water-tight with out producing any appreciable attrition. On reversing the direction of rotation of the drum 7 a vacuum is produced in the slot 28, and the paddle is forced thereinto rendering the pump inoperative, and thereby avoiding the serious injuries which usually arise from a reversal of the direction of rotation. 1 g

In themodified form of the improved pump shown in Figs. 5 and 6, the casing 1 and the drum 7 form two-working chambers 43 and 44, whereof the cylindrical surfaces 46 are symmetric with the drum 7. The working chambers 4344 communicate with suction and discharge chambers. In the chamber 44 suction is transmitted by the pipe 2 and the discharge by the chamber 37 which communicates with the conduit 36 and the discharge pipe 3.

The liquid enters the working chamber 43 through the chamber 34 communicating through conduit 33 with the suction pipe 2,

andthe discharge end of the working chamber 43 communicates directly with discharge pipe 3. Therefore, the liquid suction pipe 2 communicates with all working chambers and the same applies to the discharge pipe 3.

The surfaces 46 of the working chambers mer e into the surfaces 49, 50 forming the dear? points of the addles, the latter surfaces merging into t e eccentric surfaces 47, 48, all of these surfaces forming a unitary cylindrical inclosure for the drum.

more t an two working chambers, care being taken to properly balance the pressures before described without in any way departing from the scope of this invention.

What I claim is:

1. In a rotary pump, the combination with a casing having inlet and outlet orts for the liquid fluid, of a rotary drum orming with the casing a working chamber, said drum provided in its periphery with a plurality of slots inclined relatively to the corresponding radii of the drum, a plurality of paddles adapted to slide in said slots, each of the slots communicating in its lower portion with the exterior of the drum and said paddles being free to engage against the drum only by the combined action of centrifugal force and of the force developed by the friction between the end of the paddle and the casing.

2. In a rotary pump the combination with a casing having inlet and outlet ports for the liquid, of a rotary drum provided in its periphery with a plurality of slots inclined in relation to the corresponding radii of the drum, a plurality of free paddles with the ends beveled which slide in said slots, said casing and drum forming a plurality of working chambers each one of which communicates by one end with the inlet ort of the liquid and by the other end with the discharge port.

3. In a rotary pump, the combination with a casing having inlet and outlet ports, of a rotary drum provided in its periphery with a plurality of slots, a plurality of free paddles with beveled ends in said slots adapted to engage against the inner surface of the casing to propel the liquid, each slot forming with its corresponding radius an angle which increases with decrease in the peripheral velocity of the drum, said slots being cut away at their forward ends, and each havin a longitudinal groove extending to the ottom of the slot, said casing forming in combination with the drum a plurality of working chambers, each one of outlet port, each working surface being a formed in its central part by a cylindrical surface concentric with the drum, and at both ends by surfaces extending from the contact point between the casing and the drum to the surface of the working chamher. The ump may, of course, be formed with In testimony whereof, I aflix my signature.

FRANCISCO, PRAT BOSCH. 

